群集
ぐんしゅう · gunshuu · JLPT N1 · noun
group
群 — 君 jūn (phonetic) + 羊 sheep (semantic)
群 is a phono-semantic compound. The 羊 (sheep) component gives the meaning — sheep naturally gather in flocks — while 君 (jūn) supplies the sound. From the literal sense of a flock, the meaning broadened to any group, crowd, or cluster of people or things.
集 — bird 隹 on top of tree 木
集 is an ideograph showing a bird (隹) perched on a tree (木). The original form depicted three birds gathering on a tree, later simplified to one. From 'birds flocking together' it extended to mean 'gather, collect, assemble,' and by extension 'collection' or 'volume' of writings.